DS-2CD2032-I laggy streaming to Android all within TRUCK

So I recently received a Promaster PMC for work without rear windows. What a pleasure not knowing how fast someone directly behind me is going when I'd like to change lanes! Or if they also want to change into the other lane as well. I had a Hivision DS-2CD2032-I I wasn't using so I mounted it on the roof rack, and temporarily dropped the wires (just reached) through the rear door gasket.

I rigged two power connectors (easy since they use a standard plug) to the rear 12V outlet and plugged in the camera and an unused Netgear wifi router I had laying around to the lan port on the camera. I also had a spare android phone I had lying around so I installed the ONVIF camera viewing app on it. I Powered up the Netgear and associated the wifi. I Added the camera to the app and was happy as a pig in sh!t cuz it worked! Only problem I'm having is it's a bit laggy, I really want real-time video. I've tried with a faster tablet and 5G wifi but it's not affecting the video enough. I also tried a new TP-LINK G50 router but wifi doesn't seem to be the issue. I lowered the resolution on the camera to 1280x720, adjusted frame rates from 30 to 20 but the problem is after anywhere from 10-30 minutes the video is falling behind. I stop at a traffic light and the video catches up from 1-5 seconds later. I also tried other free apps but they were much worse. Even the HIK ivms4500 app does it only sooner.